Hi Stacie, welcome to the forum.
It's always a good idea to research each specie of fish before you purchase. Clown loaches will outgrow your tank unfortunately. A small pleco would work in your tank, like a bristlenose or clown place. Common plecos get way too big. Always consider the adult size of the fish before buying. You may want to see if your fish store will take the loaches back in exchange for a bristlenose pleco. Puffer fish don't do well with other species. They will nip them all to death. Good luck!